Download MBBS Anatomy PPT 19 Scapular And Back Region Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Human Anatomy ppt lectures Topic 19 Scapular And Back Region Notes. - anatomy ppt free download human anatomy ppt lectures, medicine notes ppt, anatomy handwritten notes pdf, mbbs 1st year anatomy notes pdf download, best anatomy notes pdf, human anatomy notes pdf, anatomy easy notes pdf, anatomy notes online, anatomy short notes, Anatomy ppt, Powerpoint Presentations and lecture notes.




Muscles Connecting the Upper

Limb to the Vertebral Column

Movements of Scapula

Movements of Scapula


Movements of Scapula

Movements of Scapula

Arranged in two layers

Layer 1st

a. Trapezus

b. Latissimus dorsi

Layer 2nd

a. Levator scapulae

b. Rhomboideus major

and minor




Trapezius

Origin

? Occipital bone(external occiptal

protuberunce), superior nuchal

line, ligamentum nuchae, spine of

seventh cervical vertebra, spines

of all thoracic vertebrae and their

supraspinous ligament

Insertion

? Upper fibers into posterior border

of lateral third of clavicle

? middle fibres- medial border of

acromion and upper lip of crest of

spine

? lower fibers pass upward and

laterally and insert on medial end

of spine of scapula

Trapezius

Nerve Supply

? Spinal part of accessory nerve

(motor) and ventral rami of C3

and 4 (sensory- proprioceptive)

Action

? Upper fibers along with levator

scapulae elevate the scapula;

? middle fibers with rhomboids

pull scapula medially (retracts);

? lower fibers pull medial border of

scapula downward , so upper and

lower fibres acting together

rotate scapula-glenoid cavity face

upward assisted by lower 5

digitations of serratus anterior

Latissimus dorsi

Origin

? Iliac crest, lumbar fascia, spines of

lower six thoracic vertebrae(T7-

T12), lower three or four ribs, and

inferior angle of scapula (5)

Insertion

? Floor of bicipital groove of

humerus (1)

Nerve Supply

? Thoracodorsal nerve

? C6, 7, 8,

Action

? Extends, adducts, and medially

rotates the arm (3)

? Its called the climbing muscle

? Raising of the trunk above the arm

Levator scapulae

Origin

? Transverse processes of first fourth cervical

vertebrae (1)

Insertion

? Medial border of scapula (1)

Nerve supply

? C3 and 4 and dorsal scapular nerve

? C3, 4, 5

Action

? Raises medial border of scapula


ligamentum nuchae

The ligamentum nuchae is a

large median ligament

composed of tendons and

fascia located between the

posterior muscles of the

neck. It covers the spines of

C1 to C6 vertebrae. It is a

superior and posterior

extension of the

supraspinous ligamen

Rhomboid minor

Origin

? Ligamentum nuchae and

spines of seventh cervical

and first thoracic vertebrae

(3)

Insertion

? Medial border of scapula (1)

Nerve supply

? Dorsal scapular nerve C4, 5

Rhomboid major

Origin
? Second to fifth thoracic spines
Insertion
? Medial border of scapula (1)

Nerve supply
? Dorsal scapular nerve C4, 5

Action
? Retract scapula
? The rhomboids work collectively with the

levator scapulae muscles to elevate the

medial border of the scapula, downwardly

rotating the scapula with respect to the

glenohumeral joint.

Muscles Connecting the Scapula

to the Humerus


Deltoid

Origin

? Lateral third of clavicle, acromion, spine of

scapula

Insertion

? Middle of lateral surface of shaft of humerus

Nerve supply

? Axillary nerve C5, 6

Action

? Middle fibers Abducts arm; anterior fibers flex

and medially rotate arm; posterior fibers

extend and laterally rotate arm

? Abduction from 15-90 degrees

Intramuscular Injection


Structures under cover of Deltoid

BONE- Upper part humerus, coracoid process
,greater tubercle, lesser tubercle Intertuberculus

sulcus

Bursa- Subdeltoid , subacromial bursa
Muscles ? attached around shoulder joint
Vessel- Ant and Post circumflex humeral vessel
Nerves- Axillary

Supraspinatus

Origin

? Supraspinous fossa of scapula

Insertion

? Greater tuberosity of

humerus; capsule of shoulder

joint

Nerve supply

? Suprascapular nerve 5, 6

Action

? Abducts arm and stabilizes

shoulder joint

? Initiation of abduction 0-15

degrees

Infraspinatus

Origin

? Infraspinous fossa of scapula

Insertion

? Middle impression of greater

tubercle of humerus; capsule

of shoulder joint

Nerve supply

? Suprascapular nerve after

passing through spino-glenoid

notch 5, 6

Action

? Lateral y rotates arm and

stabilizes shoulder joint


Teres major

Origin

? Lower third of lateral border of

scapula

Insertion

? Medial lip of bicipital groove of

humerus

Nerve supply

? Lower subscapular nerve C6, 7

Action

? Medially rotates and adducts arm

and stabilizes shoulder joint

Teres minor

Origin

? Upper two thirds of lateral border

of scapula

Insertion

? Greater tuberosity of humerus;

capsule of shoulder joint

Nerve supply

? Axillary nerve (C4), C5, 6

Action

? Laterally rotates arm and

stabilizes shoulder joint

Subscapularis

Origin

? Subscapular fossa

Insertion

? Lesser tuberosity of humerus

Nerve supply

? Upper and lower subscapular

nerves C5, 6, 7

Action

? Medially rotates arm and stabilizes

shoulder joint

Rotator Cuff

? The rotator cuff is the name

given to the tendons of the

subscapularis, supraspinatus,

infraspinatus, and teres minor

muscles

? are fused to the underlying

capsule of the shoulder joint

? stabilizing the shoulder joint

? The cuff is deficient inferiorly,

and this is a site of potential

weakness.




Rotator Cuff




Axillary Nerve

? The axil ary nerve arises from the

posterior cord of the brachial

plexus (C5 and 6) in the axil a

? It passes backward and enters

the quadrangular space with the

posterior circumflex humeral

artery

? As the nerve passes through the

space, it comes into close

relationship with the inferior

aspect of the capsule of the

shoulder joint and with the

medial side of the surgical neck

of the humerus

? It terminates by dividing into

anterior and posterior branches


Axillary Nerve

? branches:

? An articular branch to the

shoulder joint

? An anterior terminal

branch, which winds

around the surgical neck

of the humerus beneath

the deltoid muscle; it

supplies the deltoid and

the skin that covers its

lower part.

Axillary Nerve

? A posterior terminal branch, which gives off

a branch to the teres minor muscle and a

few branches to the deltoid, then emerges

from the posterior border of the deltoid as

the upper lateral cutaneous nerve of the

arm

? The axillary nerve can be injured in

dislocations of the shoulder joint

Suprascapular nerve

Arterial Anastomosis Around the

Shoulder Joint

? The extreme mobility of the

shoulder joint may result in

kinking of the axillary artery

and a temporary occlusion

of its lumen

? To compensate for this, an

important arterial

anastomosis exists between

the branches of the

subclavian artery and the

axillary artery

? ensuring that an adequate

blood flow takes place into

the upper limb irrespective

of the position of the arm


Arterial Anastomosis Around the Shoulder Joint

Branches from the Subclavian Artery

? The suprascapular artery, which is

distributed to the supraspinous and

infraspinous fossae of the scapula

? The superficial or transverse cervical

artery, which gives off a deep branch that

runs down the medial border of the

scapula

Branches from the Axil ary Artery

? The subscapular artery and its circumflex

scapular branch supply the subscapular

and infraspinous fossae of the scapula,

respectively.

? The anterior circumflex humeral artery

? The posterior circumflex humeral artery

? Both the circumflex arteries form an

anastomosing circle around the surgical

neck of the humerus

Triangle Of Auscultation

Boundaries-

Below- Horizontal fibres

of latissimus dorsi

Medially- lateral border

of trapezius

Laterally- vertebral

border of scapula

Floor ? 6th and 7th rib

Apex of lower lobe of

both lungs lie beneath

this triangle

Scapular Fracture


Is there any problem ?
MCQ

? Injury to which of the following nerve leads to

winging of scapula

a) Long thoracic nerve
b) Thoracodorsal nerve
c) Suprascapular nerve
d) Dorsal scapular nerve

MCQ

? Which of the following group of muscle acts as

lateral rotator of shoulder joint

a) Teres minor and infraspinatus
b) Teres minor and teres major
c) Supraspinatus and infraspinatus
d) Serratus anterior and rhomboids

MCQ

? Which of the following group of muscle acts as

lateral rotator of shoulder joint

a) Teres minor and infraspinatus
b) Teres minor and teres major
c) Supraspinatus and infraspinatus
d) Serratus anterior and rhomboids

This post was last modified on 05 April 2022